Review of the new Magpul PDR-C. This is an awesome little rifle, check it out.
ps. I did find I could use the midcaps when I ground down the back of the magazines, not really happy about having to do that but at least it works.
Pros
+Full carbine barrel with a tiny footprint
+Uses M4 mags
+Quick spring change
+High quality build
+Two stage trigger
Cons
-Most midcaps and lowcaps need modification to work
-Mag release tight
-Small Battery compartment
Followup: I did grind down one of my midcaps and it fit fine, but I think it’s pretty extreme to expect people to grind their mags down just to use them with this.